The CP draft shared-KV path only needs this rank's local draft tokens, but the previous compatibility path embedded the full prompt before CP-splitting. For long MTP/EAGLE prefill this recreates the large hidden activation that CP shared KV is trying to avoid.\n\nThis pads local draft input ids to the per-rank max token count recorded in NSA CP metadata, embeds the padded local tensor, then trims back to the true local length. That keeps rank shapes compatible while avoiding full-prompt embedding on every rank. Missing or stale metadata keeps the existing full-embedding fallback.\n\nConstraint: CP ranks can own uneven token counts, so the local embedding path needs a rank-uniform padded shape.\nRejected: Pad local ids to the full prompt length | this preserves compatibility but loses the intended memory reduction.\nConfidence: medium\nScope-risk: moderate\nDirective: Do not remove the full-embedding fallback unless all CP draft metadata producers guarantee max_rank_len for every prefill path.\nTested: g0034 container py_compile for utils.py and deepseek_nextn.py; g0034 container pytest -q test/registered/unit/layers/test_nsa_cp_utils.py => 25 passed, 5 warnings.\nNot-tested: Full distributed E2E with HiCache cache-hit MTP accept-length recovery.
Unit Tests
Component-level tests that do not launch a server or load model weights. Tests can use CPU or GPU — the key criterion is no server process.
Quick Start
- Find the source file under
python/sglang/srt/. - Create the corresponding test here, mirroring the source tree:
srt/mem_cache/radix_cache.py → unit/mem_cache/test_radix_cache.py srt/sampling/sampling_params.py → unit/sampling/test_sampling_params.py - Register for CI at the top of the file (after imports, before test classes):
from sglang.test.ci.ci_register import register_cpu_ci register_cpu_ci(est_time=5, suite="stage-a-test-cpu") # or: register_cuda_ci(est_time=10, suite="stage-b-test-1-gpu-small") - Run locally:
pytest test/registered/unit/ -v # all unit tests pytest test/registered/unit/mem_cache/ -v # one module - Run with coverage:
# summary pytest test/registered/unit/ --cov --cov-config=.coveragerc -v # PR incremental check (require ≥60% on changed lines) pytest test/registered/unit/ --cov --cov-config=.coveragerc --cov-report=xml diff-cover coverage.xml --compare-branch=origin/main --fail-under=60
Example
"""Unit tests for <module> — no server, no model loading."""
from sglang.test.ci.ci_register import register_cpu_ci
register_cpu_ci(est_time=5, suite="stage-a-test-cpu")
import unittest
from sglang.srt.<module> import TargetClass
from sglang.test.test_utils import CustomTestCase
class TestTargetClass(CustomTestCase):
def test_basic_behavior(self):
obj = TargetClass(...)
self.assertEqual(obj.method(), expected)
if __name__ == "__main__":
unittest.main()
Rules
- No
popen_launch_server()orEngine(...). - No model weight loading.
- Use
CustomTestCase(fromsglang.test.test_utils, adds CI retry). - Use
unittest.mockfor dependencies that are expensive to construct.